AMBER Archive (2002)

Subject: Re: What is the atoms limit for Amber 7?

From: David Case (case_at_scripps.edu)
Date: Wed Mar 27 2002 - 17:45:44 CST


On Wed, Mar 27, 2002, William Wei wrote:
>
> Could anybody tell me what is the atom limit under Amber 7 (after solvated)
> while we do minimization or dynamics? In amber 6, I think it is 99999. Thank
> you very much.

Amber 7 *should* work up to 1 million atoms, but that would be so slow as
to not make much sense. We have test cases (see, e.g.
benchmarks/rt_polymerase) that are about 150,000 atoms. I don't know
that anybody has practical experience with systems that are much larger
than this.

Note that to even get close to 1 million atoms, you would need a machine
with a fair amount of memory: for example, the pair list alone for a
periodic system with 500,000 atoms would consume 600 Mbytes of memory.

...hope this helps...dac

-- 

================================================================== David A. Case | e-mail: case_at_scripps.edu Dept. of Molecular Biology, TPC15 | fax: +1-858-784-8896 The Scripps Research Institute | phone: +1-858-784-9768 10550 N. Torrey Pines Rd. | home page: La Jolla CA 92037 USA | http://www.scripps.edu/case ==================================================================